Skeletal System

Axial Division

The Axial Skeleton You will see that each bone has special features

(overviewed in section I below) that provide

Sites of Attachment (for muscles, ligaments,

tendons, etc.) and Sites of Passage (for blood

vessels and nerves).

Study the prefixes, suffixes, and roots from

Lecture 1. These terms are used repeatedly

during the remainder of the course to describe

various parts of all of the major systems.

STUDY and KNOW these word components.

They will be an enormous aid in learning the

terms of GROSS Anatomy.

• From this point on, there is no substitute for STUDYING.

Do not do it all in one sitting. Constant review and

quizzing each other is the best way to learn it and know

it.

• One super way to learn all of the terms you are about to

be bombarded with is to make 3'X 5' FLASH CARDS.

Write the term on one side and where it is located on the

other. These are extremely useful when it comes to

quizzing yourself in the lab and certainly in reviewing for

quiz/midterm/final. The process of making the cards

themselves is very didactic. I cannot overemphasize

how useful flashcards can be in learning anatomical

terminology.

I. Different Bone Markings -

Essential Terminology Depressions and Openings

A. fissure-cleft-like opening between adjacent

parts of bones through which vessels & nerves

pass

B. foramen-hole through which blood vessels,

nerves, ligaments can pass

C. meatus-tunnel-like passageway through a bone

D. sinus-cavity within a bone with narrow

opening

E. sulcus-groove or depression that

accommodates a soft structure such as

vessels, nerve, or tendon

F. fossa-depression in/on a bone; generally at

a joint

G. process-prominent projection or point of

attachment

Articular Processes (of the

joints)

H. condyle-large, rounded articular

(joint) prominence

I. head-rounded articular projection

supported by a more constricted

portion of a bone (neck)

J. facet-smooth, flat surface on a bone

Processes for Attachment

(tendons, ligaments, etc.)

K. tubercle-small, rounded process

L. tuberosity-large, rounded, usually rough process

M. trochanter-large, blunt projection; only on the femur

N. line-less prominent ridge than a crest

O. spine-sharp, slender process

P. epicondyle-prominence found "above" a condyle

II. Curvature of the Vertebral

Column

A. Normal Curves in Vertebral Column

1. cervical curve - concave posteriorly

2. thoracic curve - convex posteriorly

3. lumbar curve - concave posteriorly

4. sacral-coccygeal curve - convex posteriorly

B. Abnormal Curves of the Vertebral

Column

1. kyphosis-exaggerated thoracic curve

(hunchback)

2. lordosis - exaggerated lumbar curve

(slumping)

3. scoliosis-S-shaped deviation out of

midsagittal plane

III. Identifying

Characteristics of Different

Vertebrae

A. cervical * C1 (atlas) no body, no spine

* C2 (axis) bifid spine, dens (head)

* C3-6 bifid spine

* C7 non-bifid spine, bulges from

lower neck

* transverse foramen vessel+nerve)

*vertebral foramen (down->smaller)

B. thoracic * T1 sup. whole facet : inf. demifacet

* T2-8 two demifacets; sup. large/inf.

small

* T9 single superior demifacet

* T10-12 whole facet for individual rib

* long, inferior-directed spinous

processes

* transverse processes are long and

heavy

C. lumbar * all have largest, thickest bodies

* spinous processes are oblong and heavy

D. sacral * 5 bones fused at middle age to

form sacrum

E. Coccygeal * 3/5 bones fused to form coccyx

IV. Intervertebral Disc

A. Functions

1. absorb stress/shock on the vertebral column

2. provide surface for vertebra to twist

B. Structure

1. annulus fibrosus - outer ring of fibrocartilage

2. nucleus pulposus - inner structure, highly

elastic

C. Herniated Disc

1. nucleus pulposus ruptures through the fibrocartilage

2. generally ruptures at L3-5 (lower back slipped disc)

3. most often occurs in posterior direction

4. can compress spinal nerves and spinal cord